The present invention relates to a flushing device for a channel, and especially to a surge flushing device for a wastewater channel with a flushing blade that can be moved essentially perpendicular to the flow direction of the liquid in the channel, between a lowered position, in which the flushing blade contacts an arc-shaped wall area of the channel wall and related channel cross section, and a raised position, in which the flushing blade releases or opens at least one part of the channel cross section.
A surge flushing device for a wastewater channel of the type described above is known from EP 1 219 753 A2. In it, a flushing blade is used that can swivel, is mounted so that it is sealed with respect to the channel wall, is automatically controlled, and is designed with a plate shape. In a mostly empty channel, even with low wastewater flow, this creates banking and allows it to proceed as a flushing surge. The flushing blade is guided to and in the channel by a lever mechanism. A closure is provided that holds the flushing blade in the lowered position and that is unlocked by a mechanism controlled from the head water to release the flushing blade.
A surge flushing device for a wastewater channel of the type described above is also known from EP 1 475 484 A2. In that case, a further development of the surge flushing device according to the EP 1 219 753 A2 document is described. It is distinguished in that a lift element works together with the lever arms of a parallel lever, connected in force and movement, for actuating the flushing flap/flushing blade. In the flushing operation, the flushing flap is driven out over the water level in the channel by the lift element. Because of this, the skimming wall effect on the flushing flap is eliminated, and the floating substances that are carried along on the water surface in the wastewater flow can pass the flushing flap unimpeded.